Installation and method for the conversion of heat into mechanical energy

ABSTRACT

An installation and method for the conversion of thermal energy into mechanical energy. The installation includes at least two closed containers, a converter for the conversion of flow energy into mechanical energy, a switching system as well as a supply line, a discharge line and a heat supply system. Each time, the converter is supplied with a fluid under high pressure and temperature from one container and the temperature-reduced fluid is then collected in another container. As soon as the other container is filled and the first container becomes empty, these containers are exchanged or replaced by other containers.

The present invention relates to an installation, as well as a method, for the conversion of heat into mechanical energy.

Installations and methods which convert heat into mechanical energy are known in the present art. Such installations and methods are often used for generating electricity (whereby a generator is connected which converts the mechanical energy into electricity) in order to use thermal energy that would otherwise remain unused. Such thermal energy is often present in cooling water and waste gases. Such thermal energy is also present in ground-water. The use of solar radiation is also known. It is also known that stone, asphalt and other such materials have the properties to retain heat under the effects of solar radiation and solar heat. Likewise, it is also known that this solar heat can be extracted from stone and asphalt, for example, by providing them with water-containing pipes that pass through them.

Although installations and methods for converting heat into mechanical energy generally use available heat, most often residual heat, the efficiency of such conversion processes still remains significant. Because the effective yield from the conversion of heat into mechanical energy or electricity leaves a lot to be desired, it is not often used in practice, although processes for this purpose are known. It clearly remains practical, especially in the use of available (residual heat) for the purpose of heating processes or buildings.

When heat is converted to mechanical energy, this generally requires a transfer medium. This transfer medium can be a fluid which is circulated in a circuit by means of pumps. The liquid is then heated to a higher energy level with a higher pressure and temperature by means of available heat, lead through a converter in which the energy level drops, in particular the temperature and pressure, and then returned via a pump or compressor. This process is not efficient since the pump or compressor requires just as much or more energy to operate than the mechanical energy that is generated in the converter.

The object of the present invention is to provide an installation and method for the conversion of heat into mechanical energy, using a transfer medium in the form of a fluid, with which such a process can be efficiently achieved.

As regards the installation, this object according to the invention can be achieved by providing an installation for the conversion of heat into mechanical energy, whereby the installation comprises:

at least two closed containers for containing a fluid;

a converter for the conversion of flow energy into mechanical energy;

a switching system;

a supply line with an inlet end section and an outlet end section;

a discharge line with an inlet end section and an outlet end section;

a heat supply system;

whereby the inlet end section of the supply line is connected to the switching system for the receipt of fluid from the switching system; whereby the outlet end section of the supply line is connected to the converter for supplying the fluid to the converter; whereby the inlet end section of the discharge line is connected to the converter for discharging the fluid from the converter; whereby the outlet end section of the discharge line is connected to the switching system for supplying the fluid to the switching system; whereby the heat supply system is made connectable to each of the containers via the switching system for heating the fluid in said containers; whereby each container is made connectable via the switching system to the supply line for the supply of fluid to the converter and to the discharge line for receiving the fluid discharged from the converter; whereby the switching system is switchable between at least two switching positions; whereby the switching system is arranged so that, when switching from one switching position to another, it repeatedly connects other containers than those in the previous switching position to the supply line and/or discharge line; whereby, on the one hand, the switching system is further arranged in order to connect in each switching position at least one of the containers to the heat supply system for heating the fluid in said container and, on the other hand to the supply line for the supply of the fluid to the converter, whereas, at the same time, another of those containers is disengaged from the heat supply system and connected to the discharge line in order to collect the fluid discharged from the converter.

The process that takes place in the installation is briefly as follows: at the high pressure side of the process there is a closed container filled with fluid. By heating this fluid in the closed container by means of available (residual) heat, the temperature and the pressure in that container increase. Here, a portion of the fluid in the container evaporates. The pressure and temperature in the container increase. This pressure will force fluid, in particular liquid-state fluid, from the container to the converter via a supply line. A fluid then arrives at the converter with a relatively high level of flow energy, with a relatively high temperature and pressure. This flow energy is then converted in the converter to mechanical energy, whereby the level of the flow energy (temperature and/or pressure) present in the fluid will drop. The fluid with the low energy level originating from the converter is then collected at the low pressure side in another container. When the container at the high pressure side is empty, at least when the fluid contained therein drops to below the lower threshold, and/or when the container on the low pressure side is full, at least when the liquid level of the fluid contained therein exceeds an upper threshold, the container at the high pressure side or the container at the low pressure side can be exchanged, either by a full or an empty container respectively. When the process is applied with the use of two containers, this then means the immediate exchange of the containers at the low and the high pressure side.

The installation according to the invention is based on the principle that in the previously described circuit the pump or compressor used for pumping back the fluid from the low pressure side to the high pressure side is omitted and substituted by two or more closed containers which can be mutually interchanged in order to supply fluid at the high pressure side to the converter, or to collect fluid originating from the converter at the low pressure side. When a container at the high pressure side is empty, this can then be exchanged with a filled container at the low pressure side. This therefore changes the continual circuit process, in which a pump or compressor is used, into an interrupted circuit process. Compared with a pump or a compressor, the exchange of the containers requires very little or no energy. The containers do not need to be physically moved, but can be connected at specific desired times by means of a switching system to the high pressure side or to the low pressure side of the process.

According to the invention it is beneficial, when increasing the energy level of the fluid supplied to the converter, if the supply line is provided with an evaporator for evaporating liquid-state fluid which is transported up and down the line to a gaseous or vapour-like fluid. According to a further advantageous embodiment, this evaporator comprises a heat-exchanger connected to the heat supply system. In this manner therefore, evaporation can be achieved using the same available heat source as that with which the container at the high pressure side is heated.

According to a further embodiment, it is advantageous if the discharge line is provided with a cooler for cooling the fluid flowing through the discharge line. In this manner, the saturated gaseous particles of the fluid are easily evaporated. The process can be controlled more effectively with the use of such a cooler. A further advantage of the invention is when the cooler is a heat-exchanger and when the cooler is arranged to supply the heat-exchanger with a cooling medium, the temperature of which is determined by the ambient temperature. The ambient temperature can be the temperature of the air, surface water, seawater, a rock formation, the ground etc. Therefore, in this way, the ambient temperature is used to cool. The ambient temperature is essentially a freely available medium which enables one to use essentially freely available cooling energy.

According to an alternative embodiment, each container can act cooperatively with a heater positioned in a space isolated in respect of, or at least for a substantial part of the internal volume of the respective container, from which heaters each respective container is connected to the switching system. By definition, each isolated space contains a relatively small amount of fluid, only a relatively small amount of which is required for the purpose of heating. This is beneficial in that a considerable expansion of gaseous fluid can be obtained with only a relatively small amount of energy. In this way, a liquid or gas can be supplied in an efficient manner to the converter.

In conjunction herewith, each heater can be positioned externally to the container and be connected to the container by means of connecting lines; however, it is also possible to isolate said space within the interior of the container in relation to the remaining space therein.

Furthermore, each container can act cooperatively with a cooler, which is preferably present within the container. This cooler can be in continual operation, whereby said cooler can cool the gaseous phase directly, as soon as the fluid level in the container is so low that the cooler is disengaged. In this way a rapid cooling of the gaseous phase is achieved, which is beneficial to a short cycle period. Subsequently, the respective cooler can then be quickly re-filled with liquid from another container as a result of the low pressure thus achieved.

The invention relates further to an installation for the conversion of thermal energy into mechanical energy, whereby the installation comprises:

at least two closed containers for containing a fluid;

a converter for the converting flow energy into mechanical energy;

a switching system;

a supply line with an inlet end section and an outlet end section;

a discharge line with an inlet end section and an outlet end section;

a heat supply system;

whereby the inlet end section of the supply line is connected to the switching system for the receipt of fluid from the switching system; whereby the outlet end section of the supply line is connected to the converter for supplying the converter with the fluid; whereby the inlet end section of the discharge line is connected to the converter for discharging the fluid from the converter; whereby the outlet end section of the discharge line is connected to the switching system for supplying the switching system with the fluid; whereby each container acts cooperatively with a heater; whereby the heat supply system is made connectable via the switching system with each of the heaters for heating the fluid in said containers; whereby each container is made connectable through the switching system, with the supply line for the supply of fluid to the converter and with the discharge line for the receipt of the fluid discharged from the converter; whereby the switching system is switchable between at least two switching positions; whereby the switching system is arranged so that, when switching from one position to another, it repeatedly connects other containers than those in the previous switching position to the supply line and/or discharge line; whereby, on the one hand, the switching system is further arranged in order to connect, in each switching position, the heater of at least one of the containers to the heat supply system for heating the fluid in said container and, on the other hand, to connect that container to the supply line for the supply of the fluid to the converter, whereas, at the same time, another of those heaters is disengaged from the heat supply system and the other of those containers is connected to the discharge line in order to collect the fluid discharged from the converter.

This installation may be provided with a heat discharge system;

whereby each container acts cooperatively with a cooler; whereby the heat discharge system is connected to each of the coolers of the containers for cooling the fluid in said containers.

According to a further embodiment of the invention, the converter comprises a turbine, in particular a liquid turbine. Gaseous and/or liquid flows with high efficiencies can be converted into mechanical energy by the use of a turbine.

According to a further embodiment of the invention, the converter comprises a flywheel. This enables the converter to compensate for any interruptions or irregularities in the supply of fluid.

According to a further aspect, the invention relates to an assembly comprising an installation according to the invention, including an electricity generator, whereby the generator is coupled to the converter for generating electricity from the mechanical energy generated from the converter.

According to a further aspect, the invention relates to the use of an installation according to the invention for the conversion of thermal energy into mechanical energy.

According to yet another aspect, the invention relates to the use of an assembly according to the invention for the conversion of thermal energy into electricity.

As regards the method, the object of the invention, according to yet another aspect of the invention, is achieved by applying a method for the conversion of heat into mechanical energy, whereby the method is applied with the use of at least two containers,

whereby the method comprises the following steps: a) the heating of a liquid-containing fluid present in a first said container, by means of a medium with a high temperature, in such a manner that a portion of the liquid is converted to a gaseous phase and the pressure in the container increases; b) the use of the increase in pressure in the first container in order to transfer the fluid, particularly a liquid-phase fluid, from the first container to a converter; c) the conversion in the converter of flow energy, present in the fluid supplied to the converter, into mechanical energy; d) the extraction of the energy-reduced fluid to a second said container; e) the collection in the second container of all the fluid extracted from the converter; f) the exchange of this first container with another container with a higher liquid level when the liquid level of the first container drops below a certain predetermined lower threshold; g] the exchange of the container in use by another container with a lower filling level when the liquid level of the second container has exceeded a predetermined upper threshold; whereby a container made available in step g] is used in step f]; whereby a container made available in step f] is used in step g].

Further advantageous embodiments of this method are described in the claims 17-21. With regard to the further description of the method according to the invention, as well as advantageous embodiments thereof, reference should be made to the aforementioned, as well as to the description of the figures given hereinafter.

The fluid used in the installation and by the method according to the invention can essentially be any fluid which is evaporable from its liquid state. The liquid may be water, for example. In particular, the fluid will be a fluid typically applied in cooling systems, such as R407C, R134a, Freon and Freon-substitues etc.

The installation and assembly according to the invention are highly suited to being constructed as containers in a modular fashion. Here, conceivable containers would be, for example, freight containers and sea containers, such as those used in road transport, sea transport or for other means of transport over water.

When the installation according to the invention is applied with the use of high pressure steam—i.e. steam with a pressure exceeding 70 bar, for example, higher than 130 bar (for example with a pressure of 180 bar and a temperature of 540° C.)-considerably higher efficiency rates are achievable than in conventional high-pressure steam systems.

The present invention will be described hereinafter in more detail with reference to the accompanying drawing, in which:

FIG. 1 is a highly schematic representation of an installation according to the invention;

FIG. 2 is also a schematic representation, in this case however, of an alternative embodiment of the lower section of the installation according to FIG. 1 indicated by parentheses II;

FIG. 3 shows a third embodiment.

FIG. 1 shows an installation 1 according to the invention. Here, 2 indicates a converter for the conversion of flow energy into mechanical energy, 3 indicates a generator 3 for generating electricity from the axle 16 driven by converter 2, 4 indicates an optional cooling system which is optionally operable with the use of a heat-exchanger 5, 6 indicates an optional evaporator to which the energy required for evaporation is optionally supplied by means of heat exchanger 7, 8 indicates a switching system, 9 and 11 indicate closed containers, and 10 and 12 indicate heat-exchangers.

The switching system 8 here is shown schematically as a block that can be caused to move between two positions in accordance with the twin arrow 84, in which a multiple of connecting channels 85 are positioned, illustrated in inclined positions, which, depending on the position of the switching system 8 connect the lines 20, 30, 40 and 50, lying on the upper surface of the block, either with the lines 21, 31, 41, and 51 respectively, or with the lines 22, 32, 42 and 52 respectively.

Line 20 is indicated together with the supply line and connects the switching system 8 with the inlet 13 of the converter 2. This supply line 20 can optionally comprise an evaporator 6 in order to evaporate the liquid-state fluid flowing through the line 20.

Line 30 is indicated as discharge line and connects the outlet 14 of the converter 2 with the switching system 8. This discharge line 30 may optionally comprise a cooler 4 for cooling the fluid flowing through the discharge line 30.

When a fluid is supplied via the evaporator 6 through line 20 to the converter 2 (in this example a turbine) under relatively high pressure, for example 15 to 20 bar, a turbine wheel in the turbine is caused to rotate which drives an axle 16 with which electricity can be generated by a generator 3, the electricity thus generated being indicated by arrow 100. The energy-reduced fluid in the converter 2 will enter the discharge line 30 via the outlet 14 and, if necessary, can thereby be cooled by means of the cooler 4. Subsequently, in order to enable the fluid to circulate in a continual process, the discharge line 30 and the supply line 20 would need to be jointly connected via a pump or compressor. In such cases, the pump of compressor requires such a high level of power that the electricity 100 thus generated is obtained in an extremely inefficient manner. The present invention eliminates this problem by means of connecting the circuit between the discharge line 30 and the supply line 20 in a different manner.

The present invention uses at least 2 closed containers 9 and 11, the example according to FIG. 1 showing exactly 2. The closed container 9 contains a fluid which is heated by means of a heat-exchanger 10. The pressure and temperature in the closed container 9 will rise as a result of this, for example, to 15 to 20 bar and 40° C. As soon as the pressure in the closed container 9 exceeds a certain threshold value the non-return valve 91 of the installation will open and force liquid-state fluid from the closed container 9 into the line 21. The switching system 8 connects line 21 with supply line 20 and in this manner enables the liquid-state fluid to be transferred to the turbine 2 via the evaporator 6. In the turbine 2, the flow energy present in the fluid is converted into mechanical energy, in the form of a rotating axle 16, after which the energy-reduced fluid, which, for example, still has a pressure of 5 bar and a temperature of 20° C., is discharged from the converter 2 via discharge line 30. Discharge line 30 is connected to a line 32 via switching system 8, from which the energy-reduced fluid is collected in the other closed container 11. By continuing this process, the fluid level 80 in container 9 will drop and the fluid level 83 in container 11 will rise. As soon as the fluid level 80 in container 9 drops below the lower threshold 82, the container 9 is considered empty. At approximately the same time, the fluid level 83 in container 11 will exceed an upper threshold 81, after which the container 11 will be considered as full. As soon as this situation occurs, the switching system 8 will be switched from the switching position shown in FIG. 1 to another switching position by sliding the block 8 to the left. As soon as the block 8 is moved to the left, the line 22 which was closed off by the block 8 whilst in its initial position is connected to the supply line 20, the line 21 that was previously connected to supply line 20 is closed off, the line 32 that was previously connected with the discharge line 30 is closed off, and the line 31 that was previously closed off is connected to the discharge line 30. Subsequently, by heating the fluid in the container 11, which had the pressure of 5 bar and the temperature of 20° C., as given in the example, before switching took place, to the previously mentioned pressure of 15 to 20 bar and a temperature of 40° C., and by decreasing the temperature and pressure in the container 9 (for example, by means of cooling) to the level at which the pressure and temperature in container 11 was (in this example 5 bar and 20° C.) before switching, the process described hereinbefore can be repeated. The converter 2 will now be supplied from the container 11 and the energy-reduced fluid will be collected in container 9. As soon as the fluid level in container 9 has exceeded the upper threshold 81 and/or when the fluid level 83 in container 11 has dropped to beneath the lower threshold 82, the switch system 8 can be switched back to the position shown in FIG. 1. In principle, this continual switching of the switching system 8 can be infinitely repeated.

The heat required for heating the fluid in container 9 (in the position indicated in FIG. 1) or in container 11 in a different switching position, originates from the respective exchanger 10 or 12. The heat-exchangers 10 and 12 can be supplied with cooling water originating from, for example, an industrial process or an electric power station, or with groundwater, or otherwise with a warm fluid (such as a gas liquid, or gas/liquid mixture) which does not necessarily need to be water. The heat for supplying the heat-exchangers 10 and 12, for example, can also be obtained by laying a pipe system containing water within the asphalt, so that the water can absorb solar heat via the asphalt. The heat supplied for heating the fluid in container 9 or 11 is supplied via line 38 which, as shown in FIG. 1, is connected via line 40 to the switching system 8. Line 40 can be connected via the switching system 8 either with line 41 or line 42. The switching position according to FIG. 1 is line 40 connected to line 41 in order to supply the heat-exchanger 10. The return flow from the heat-exchanger 10 is returned via line 51, via switching system 8, line 50 and line 48. When the switching system 8 is set to the position to the left, the heat will supply heat-exchanger 12 via line 42 and the backflow will flow via line 52 to line 50 and line 48. As can be seen in FIG. 1, the same heat flow 38 can also be used to supply the heat-exchanger 7 in the evaporator 6. This occurs via a branch line 39. The return flow from the heat-exchanger 7 is supplied via a line 49 back to line 48.

FIG. 2 shows a schematic view of an alternative lower section of the installation 1, other than that indicated in FIG. 1 by means of parentheses II. In this alternative embodiment the switching system is indicated by 88, and in addition, the containers 110 and 101 are added, which, incidentally correspond to the containers 9 and 11. Container 100 is provided with lines 23, 33, 43 and 53 which correspond to the respective lines 21, 31, 41 and 51 of container 9 and the respective lines 22, 32, 42, and 52 of container 11. In the same manner, container 101 is provided with the respective lines 24, 34, 44 and 54. The liquid level in containers 100 and 101 is indicated by 85 and 86 respectively. For the remainder, the reference numerals used in FIG. 2 correspond to the reference numerals used in FIG. 1.

By means of the embodiment according to FIG. 2, the yield of mechanical energy or, possibly, electricity can be increased. Consequently, when the containers 9 and 11, for example, are in use for supplying the converter or for the return flow of fluid from the converter 2, the fluid in container 101, which is filled to a high level 86, can in the meantime be heated in order to bring this container 101 up to the pressure and temperature level of container 9 whilst, in the meantime, container 100 can be allowed to cool to the pressure and temperature level of container 11. Subsequently, when container 11 is full and container 9 is empty, the switching system 8 can continue switching in order to connect container 101 to the supply line 20 in order to supply converter 2 and container 100 to the discharge line 30 in order to return collected fluid. The process is then effectuated by means of the containers 100 and 101. Meanwhile, container 11 can be heated and container 9 can be cooled. As soon as container 101 becomes empty and container 100 is filled, switching may continue in order to supply converter 2 from container 11 and to receive back the fluid in container 9, whilst, in the meantime, container 100 is heated and container 101 cools. As soon as container 11 empties and/or container 9 is filled, switching can be continued, and so forth. If desired, more than four containers can be used, for example, when the time required for the transfer of the content from the container at the high pressure side to the container at the low pressure side is shorter than the time required for heating the filled container(s) to the desired heat level or cooling the empty container(s). So, in this manner, an essentially continual process can be achieved by using an appropriate number of containers.

In the alternative embodiment in FIG. 3, external heat-exchangers or heaters 102 are applied at each container 9, 11 and incorporated within the housings 103. These housings 103 are each connected to a line 104 with the upper side of the containers 9, 11 and with a line 105 with the lower side of the containers 9, 11. The volume of the housings 103 is substantially smaller than the volume of the containers 9, 11. The heaters 102, which are supplied via the lines 105 with liquid-state fluid, only need to heat a small quantity of fluid in order to reach the gaseous phase, which is supplied to the respective containers 9, 11 via the lines 104. In the containers, these gases produce an egressive effect on the liquid which, as a result, can be transported back to the converter 2 via the opened valve 91 and lines 21 and 22 respectively. Therefore, a relatively small quantity of energy, which is sufficient to heat the quantity of liquid in the housings 103, will result in the rapid egression of liquid from the containers 9, 11 by the gases obtained in the housings. The resulting expansion in the containers ensures an efficient egression of the liquid from the containers 9, 11, which liquid does not need to be heated in its entirety in order to enable that egression. This shortens the cycle period, which is advantageous to the performance of the installation. The term ‘cycle period’ is understood to mean the time required to force the liquid from the one container to the other and back again.

Additionally, a heat pump 110 is provided, which is supplied via the line 111 with a portion of the electrical energy generated by generator 3. The heat pump enables the reclamation of heat which would otherwise be discharged from the installation and be lost. The heat pump 110 absorbs heat from the heat-exchanger 5 via line 109, and transfers the heat thus absorbed to the line 38. Cooling is then supplied to the heat-exchanger via line 108.

Furthermore, the heat-exchangers 10, 12 or coolers may cool the container after the liquid has been forced out, as described hereinbefore, in order to obtain a low pressure in the interior of said container. To this end, in the exemplary embodiment of FIG. 3 these coolers 10, 12 are connected via the lines 106 to the line 109 and via the line 107 to the line 108. The coolers are therefore continually operative when the heat pump is in use. They cool the liquid in the containers 9, 11 and, as soon as the liquid level in the containers has dropped partially or entirely to below the level of the heat-exchangers 10, 12, they will immediately begin to cool the gas present above the liquid. This ensures an efficient cooling of the gas, such that a correspondingly fast drop in pressure in the containers 9, 11 occurs which is beneficial to the efficient continuation of the successive cycles of the cooling of the gas in the container in conjunction with the collection of liquid that has been forced out of the other container etc.

External heat can be supplied via the heat-exchanger to the installation via the lines 38′ and 48′. Also, even if the heat-exchanger is not in operation, external heat can be supplied to the installation via lines 38″ and 48″; in connection with the exchange of operations with or without a exchanger, appropriate switching means (not shown) can be provided for using the respective lines 38′ and 48′ or 38″ and 48″.

Although in the previous description the coolers 102 are cooled by the operation of the heat pump, this is not a requirement. Cooling by a different means may also ensure the desired cooling effect, such as cooling by means of a cold ambient environment. 

1-22. (canceled)
 23. Installation for the conversion of thermal energy into mechanical energy, whereby the installation comprises: at least two closed containers for containing a fluid; a converter for converting flow energy into mechanical energy; a switching system; a supply line with an inlet end section and an outlet end section; a discharge line with an inlet end section and an outlet end section; a heat supply system; whereby the inlet end section of the supply line is connected to the switching system for the receipt of fluid from the switching system; whereby the outlet end section of the supply line is connected to the converter for supplying the converter with the fluid; whereby the inlet end section of the discharge line is connected to the converter for discharging the fluid from the converter; whereby the outlet end section of the discharge line is connected to the switching system for supplying the switching system with the fluid; whereby the heat supply system is made connectable via the switching system with each of the containers for heating the fluid in said containers; whereby each container is made connectable via the switching system with the supply line for the supply of fluid to the converter and with the discharge line for the receipt of the fluid discharged from the converter; whereby the switching system is switchable between at least two switching positions; whereby the switching system is arranged so that, when switching from one switching position to another, it repeatedly connects other containers than those in the previous switching position to the supply line or discharge line; whereby, on the one hand, the switching system is further arranged in order to connect, in each switching position, at least one of the containers to the heat supply system for heating the fluid in said container and, on the other hand, the supply line for the supply of the fluid to the converter, whereas, at the same time, another of those containers is disengaged from the heat supply system and connected to the discharge line in order to collect the fluid discharged from the converter, whereby each container (9, 11) acts cooperatively with a heater (102) which is present in a space (103) which is isolated in relation to at least the most substantial part of the internal volume of the respective container, through which said heaters (102) each respective container (9, 11) is connected with the switching system.
 24. Installation according to claim 23, whereby the supply line is provided with an evaporator for evaporating the liquid-state fluid;
 25. Installation according to claim 24, whereby the evaporator comprises a heat-exchanger which is connected to the heat supply system.
 26. Installation according to claim 23, whereby the discharge line is provided with a cooler for cooling the fluid flowing through the discharge line.
 27. Installation according to claim 26, whereby the cooler is arranged in order to supply the heat-exchanger with the cooling medium, the temperature of which is determined by the ambient temperature.
 28. Installation according to claim 23, whereby the converter comprises a turbine, in particular a liquid turbine.
 29. Installation according to claim 23, whereby the converter comprises a flywheel.
 30. Installation according claim 23, whereby each heater (102) is positioned exterior to the container (9, 11) and is connected to the container via connection lines (104, 105).
 31. Installation according to claim 23, whereby each container (9, 11) acts cooperatively with a cooler (11, 12).
 32. Installation according to claim 23, whereby a heat pump is provided which is connected to the heat supply system and the discharge line for extracting heat from the discharge line and for the supply of the heat extracted from the discharge line to the heat supply system.
 33. Assembly comprising an installation according to claim 23, including an electricity generator, whereby the generator is coupled to the converter for generating electricity from the mechanical energy generated from the converter.
 34. Method for the conversion of thermal energy into mechanical energy, whereby the method is performed with the use of at least two containers, whereby the method comprises the following steps: a) heating a liquid-containing fluid present in a first mentioned container, by means of a medium with a high temperature, in such a manner that a portion of the liquid is converted to a gaseous phase and the pressure in the container increases; b) increasing the pressure in the first container in order to transfer the liquid-phase fluid, such as a liquid-state fluid, from the first container to a converter; c) converting flow energy in the converter, present in the fluid supplied to the converter, into mechanical energy; d) discharging the energy-reduced fluid to a second said container; e) collecting in the second container all the fluid discharged from the converter; f) exchanging the first container with another container with a higher liquid level when the liquid level of the first container drops below a certain minimum level; g) exchanging the container in use with another container with a lower filling level when the liquid level of the second container has exceeded a predetermined upper threshold; whereby a container made available in a step g) is used in step f); whereby a container made available in a step f) is used in step g) whereby in step a) a portion of the liquid in the container is separated from the rest of the liquid, the separated portion is heated and whereby the gaseous phase thus obtained from the separated portion is transported back to the container.
 35. Method according to claim 34, whereby steps f) and g) take place simultaneously.
 36. Method according to claim 35, whereby the method is performed with the use of two containers which, when steps f) and g) are executed, are both mutually exchanged.
 37. Method according to claim 34, whereby the fluid is evaporated during step b).
 38. Method according to claim 34, whereby the fluid is cooled during step d). 